Keynes Country Park Geology and Landscape Heritage Trail isbn 9781904530169 The Cotswold Water Park is one of the most rapidly changing landscapes in Britain today. Sand and gravel extraction leaves large pits that are allowed to flood to create lakes, used for leisure and as wildlife havens. The gravels were deposited here by a major river system during the Ice Ages when man started to settle the area. Removal of soil and gravel has not only yielded a treasure trove of archaeological remains, but also revealed a fascinating natural history story stretching back 165 million years.